Material for protecting metals from tarnish



Dec. 9, i952 Filed July 26, 1949 6 T T 0 N M y 8 6 R A f 0 0 9 5 M O A fu l IW LUQ N a m 4 .www a AoM EH 61. H a

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I zi/venior' ROZ'GTZHPFcEw, 5 2"? at Patented Dec. 9, 1952 MATERIAL FOR PROTECTING METALS FROM TARNISH Robert H. Prew, Nashua, N. H., assignor to Nashua Corporation, Nashua, N. H., a corporation of Massachusetts Application July 26, 1949, Serial No. 106,855

4 Claims.

This invention relates to a material which may constitute a wrapper, a container wall, a lining for such a wall, or a wrapper to receive metal articles, notably those in whole or in part of silver, which are subject to tarnish from tarnishing agents in the atmosphere, notably sulphur or gases containing sulphur.

The formation on silver of the tarnish of silver sulphide is well known. It has been proposed to protect the silver by Wrapping or packaging it in a textile fabric impregnated with some agent which because of its chemical nature or its physical form, or both, will be more susceptible to attack by sulphur than the silver piece itself. A somewhat extended discussion of this subject matter will be found in the patent to Jones 1,766,646. No novel chemical action is involved in the present invention and insofar as the choice of chemical agents is concerned it may be practiced by utilizing the knowledge of the prior art as for example said patent to Jones.

While the fabric impregnated with finely divided silver oxide as described in the Jones patent is, both in theory and practice, efficient'in minimizing the tarnishing of silver, it has the disadvantage that when it operates by reaction of the silver salt with tarnishing gases such as hydrogen sulphide, the fabric becomes dirty and unattractive. In practice the invention has been utilized only with dark colors, minimizing this effect. Even among dark colors dull shades only may be used. A bright shade of a dark color could not be used.

The present invention provides a construction having an attractive texture capable of being produced in a wide variety of colors and which, while efiicient in its anti-tarnishing action, does not noticeably deteriorate in appearance.

The material embodying the invention may be used for protecting articles subject to deleterious tarnishing, such as silver tableware, (flatware socalled), hollowware for use or ornament, ornamental articles including jewelry, in all instances whether sterling silver or silver plated or having a surface partly of silver, and also silver-gilt and rhodium plate on brass or slush metal, socalled, which latter is an alloy of zinc, lead and antimony. For convenience herein I designate all such articles by the term silverware.

The invention will be well understood by reference to the following description taken in connection with the accompanying drawing wherein:

Fig. 1 is a schematic and unrealistic View showing the improved material in section; and

Fig. 2 is a diagrammatic view illustrating a method of manufacturing the same, when flexible backing is utilized.

The material of my invention in appearance has a surface resembling that of velvet and, when incorporating a flexible backing as herein specifically described, is as a whole like a piece of velvet. Referring to Fig. 1 it may comprise a backing sheet 50 which may be a textile fabric, paper, or

some other flexible sheeting having one face completely covered by a pile of upstanding filaments E2 and I 4 of textile fiber which are secured thereto by suitable adhesive It. This pile surface comprises long filaments l2 and short filaments [4 in substantially uniform relative distribution throughout the area of the fabric. The long filaments [2 are sufficiently numerous to constitute the visible face of the right side of the fabric as in the case of the pile on a piece of velvet. While the short filaments constitute a substantial proportion of the whole, the long filaments project beyond them as seen in Fig. 1 and substantially hide them. The construction may be compared to that of the pelts of certain fur-bearing animals, in which there is a fine inner fur, which is covered by longer, exposed hair.

In accordance with the invention the short pile elements 14 carry a suitable anti-tarnish agent of any desired character as, for example, finely divided silver oxide precipitated in the fibers thereof, as described in the Jones patent aforementioned. Silver oxide is believed to be most efficient and is recommended. The long filaments are substantially free from such material.

The long filaments l2 determine the exterior appearance of the material as a whole, which as already stated is that of velvet, and they may be of a bright color. Tarnishing gases readily penetrate the pile to react with the silver oxide on the short filaments. The resultant discoloration however is dissimulated by the untreated long fibers 12, which hide the discolored short filaments.

In Fig. 2 I have shown diagrammatically one manner in which the improved material may be produced on a backing ll] of textile fabric, paper, or other sheet material. A suitable material for use in forming the filaments is cut rayon flock. The short filaments It may be about one millimeter in length on the average and the long filaments about two millimeters. As illustrated diagrammatically at the right of Fig. 2, the short filaments may be impregnated with silver nitrate solution and then treated with hot sodium carbonate solution, thus precipitating silver oxide in the fibers of the flock in finely divided form,

which physical form is an important feature in their preferential susceptibility to the action of sulphur as contrasted with the solid metal of the articles which they are to protect. The flocks are then washed and dried as indicated by the legend of the drawing. Conveniently the treated short filaments and thenntreated long filamentsmay be mixed and. delivered to the distributing .7

hopper l8 of a suitable flocking machine such as is shown diagrammatically in the lower por-- tion of Fig. 2. The backing l is ,,drawn from..

the roll at the right and a roller' spreads;..the:.

adhesive IS on its face. The adhesive side passes under the hopper l8 and thegfiock; is :sha-ken:

thereon, after which the sheetaisssubjected .to'.;

the action of heaters 22 causing the flock elements to stand on end so thatuthe lower. ends.

uniformly as long pile with a shorter pile received inwardly of the outer surface of the longer:v

pile. Surplus fiock is drawn away by annex-:- haustingmechanism at. and the coatedmaterial-passes througlra drier-.26 .to. setthe-adhesive and whet-completed sheet. may then be rewoun-d.

ture--of,- the backing lll may be usedasra containen. as, a wrapper; :asa ,bag .or as a lining ,for.

-25 The-material, depending somewhaton the na- 1 ware when in the: hands ,;of the ultimate consumer-or-atany or. all stages-ofits transit from the. manufacturer to the consumer.

I am aware thatzthe invention may. be embodied in otherspecific-forms -With011tdeparting from thespirit-or essential attributes. thereof, and I therefore .desire ,the present. embodiment to be consideredqin .all respects asillustrative and-not restrictive,.as..is in fact. clearin-several matters from-,the description itse1f.. Reference, is TIC b8:

principlesv of.- the invention exemplified by the had .,to, the appended claims-v to, indicate= those particular embodiment described and ,which .I desire to secure by Letters Patent:;

I claim:

1. Material for protecting-fromtarnish silverware placed in adjacency .thereto, .comprisingv -a backingnonesfacewof which -isecovered :by. a-pile T consisting; ;of. relatively long and-relatively short textile; -;-flock in substantially uniform relative distribution throughout .thearea of -the-=backing,

theflocks being adhesively securedendwise to the face of the ;backing inupstanding position; the short flocks; retaining. in .the fibers-thereof a sub-- 4 stance which as compared with the silverware is preferentially susceptible to chemical attack by tarnishing agents in the air, the long flocks being substantially free of such substance.

2. Material for protecting from tarnish silverware placed in adjacency thereto, comprising a backinghaving relatively; short-=.and ;rela.tively long filaments secured thereto in the manner of a pile, the short filaments carrying silver in a form which will preferentially combine with the tarnishing. agentsinthe atmosphere and prevent themiJ-from combining with the silver on the surface of the silverware and the long filaments being;substantiallyiree of such substance and projecting .be'yondcthe short and substantially hiding the sames 3. Materialjorprotecting from tarnish silverware placed in adjacency thereto, comprising a backingwqhaving relatively short and relatively long filaments secured thereto in the manner of a pile, .the shortv filamentscarrying a substance which asrcompared with .the silverware isprefere. entially susceptible-Ito=chemical attack by,-the,- tarnishing agents. in ..the .atxnosphere,-: the dong fiJaments-.-being substantially free-of I such.sub-.. stance. and, projecting beyond-,theshort. and sub. stantially hiding the same.-

4, Materialfor. protecting. from .tarnishsilvere ware placed -.in .adjacency thereto, comprisingai backing ,having. one .f ace completely covered -.by' 7 a deempile-of textilel-fibenmaterialthedeep-pile concealing. a shorter pile of, textile fibenmaterial. alsosanchored to said -backing, .the .flbers oi-lther short :pileretainingtherein a substance. which.- as: compared with the silverware is preferentially subject to chemical .attack by tarnishing agents. in the air, the-long pile .being substantially free- '1 of. r such. substance.

ROBERT vH. EPREW:

REFERENCES. CITED!" Thefollowingreferences-are aof: recordinzthe file; .of.; this Datentz:

UNITED STATES PA'I'EN'IS Number Names. Date...

223,814. Pennington Jam 2'Z,-1880;= 2,003,333.. Barnard etal, J une.4,:1935..., 2,0 14,426. Dorogi l ,Sept; 17, 1935 2,136,483 Barnard z-.. NOv .v15,-,1938.J 2,358,706. Fountain u .Feb. -6, 19.45. 2,383,598... Gliden Aue.-..28,..19.45... 2,428,591 Slayter .Oct; 7,.19.47. 

1. MATERIAL FOR PROTECTING FROM TARNISH SILVER WARE PLACE IN ADJACENCY THERETO, COMPRISING A BACKING ONE FACE OF WHICH IS COVERED BY A PILE CONSISTNG OF RELATIVELY LONG AND RELATIVELY SHORT TEXTILE FLOCK IN SUBSTANTIALLY UNIFORM RELATIVE DISTRIBUTION THROUGHOUT THE AREA OF THE BACKING, THE FLOCKS BEING ADHESIVELY SECURED ENDWISE TO THE FACE OF THE BACKING IN UPSTANDING POSITION, THE SHORT FLOCKS RETAINING IN THE FIBERS THEREOF A SUBSTANCE WHICH AS COMPARED WITH THE SILVERWARE IS PREFERENTIALLY SUSCEPTIBLE TO CHEMICAL ATTACK BY TARNISHING AGENTS IN THE AIR, THE LONG FLOCKS BEING SUBSTANTIALLY FREE OF SUCH SUBSTANCE. 